Rc and RefCell

Overview

Rc<T> provides shared ownership, while RefCell<T> enables interior mutability with runtime borrow checking.

Code Example

#![allow(unused)]
fn main() {
use std::rc::Rc;
use std::cell::RefCell;

let shared_data = Rc::new(RefCell::new(vec![1, 2, 3]));

// Clone the Rc to show shared ownership
let shared_clone = Rc::clone(&shared_data);

// Modify through RefCell
shared_data.borrow_mut().push(4);

println!("Original Rc count: {}", Rc::strong_count(&shared_data));
println!("Shared data: {:?}", shared_data.borrow());
println!("Clone also sees: {:?}", shared_clone.borrow());
}

Key Concepts

• Rc: Reference counting for shared ownership (single-threaded)
• RefCell: Runtime-checked interior mutability
• Use Arc<Mutex<T>> for multi-threaded version

Learn More

• std::rc documentation
• std::cell documentation